Pyrites-furnace



E. C. BRACQ.

PYRITES FURNACE.

APPLICATION FILED Nov. 9, 1918.

Patented Mar. 30, 1920.

2 SHEET S-SHEET 1- E. C. BRACQ.

PYRITES FURNACE.

APPLICATION FILED NOV- 9,1918.

1 ,335,271 Patented Mar. 30, 1920.

2 SHEETS-SHEET 2.

Fig.4.

EMILE CONSTANT BRACQ, OF PARIS, FRANCE.

PYRITES-FURNACE.

Specification of Letters Patent.

Patented Mar. 30, 1920.

Application filed November 9, 1918. Serial No. 261,828.

To all whom itmay concern:

Be it known that I, EMILE CONSTANT BRAC a citizen of the French Republic, residing at Paris, France, have invented certain new and useful Improvements in Pyrites-Furnaces, of which the following is a specification.

Hitherto in pyrites furnaces with helical soles and scraper arms the driving mechanism prevented (in the case of four, six or more arms) the central shaft of the furnace from being withdrawn for the purpose of removing worn out or damaged scraper arms. It was therefore necessary to remove the worn out or damaged arms through openings arranged on the outer circumference of the furnace, leaving the central shaft in place.

The result was that the operation of re- ,placing a single scraping arm was always very troublesome and sometimes necessitated the stoppage of the furnace for a long time.

Moreover, it is of great advantage for furnaces of this kind (with reciprocating angular movements of the scraper arms producing great momentum) to insure the greatest stability to the mechanical driving parts.

This invention insures perfect stability of the parts and renders easy and practical removal from the furnaceof the central shaft complete with its scraper-arms, so as to carry out, away from the high temperature of the furnace, the dismantling and the fitting of any damaged scraper arms.

The accompanying drawings show the various means for attaining the'object in question. 1 In the said drawings,

Figure 1 is a sectional longitudinal elevation of the furnace, showing a furnace with helical sole provided with a detachable shaft with scraper arms and the mechanism which operates the whole,

Fig. 2 is a plan in section on the line AA of Fig. 1.

Fig. 3 is a plan of the furnace, showing the pivoting of the girders, facilitating removal of the shaft.

Fig. 4 shows the shaft during its withdrawal from the furnace.

The whole of the driving mechanism is arranged at the base of the furnace, on the brickwork of the foundations, and is constituted so that it can be introduced and removed by causing it to slide on the girders 1.

The furnace is closed at the bottom part by a collar 2 provided for the purpose and made in two parts, with inner scrapers for. the purpose of discharging any dust or residue of pyrites that may filter through. to the base, thus protecting the mechanism from dust.

The pyrites is fed into the furnace from a hopper comprising a conical chute 100 delivering into a horizontal box 101 which is connected atboth endsby ducts 102 to the uppermost part of the helical hearth. Along the floor of the boX reciprocates a rake or blade 108 which feeds the material falling on to the floor of the box, into the ducts 102 whence it drops on to the hearth and is swept along the same by scraper or rabbling arms 22 hereinafter described. The lower end of the helical hearth overlies a channel at the bottom of which is arranged a conveyer screw 3, the residue being thereby discharged directly into a truck 4. The conveyer screw is detachable.

The pivot 5 rests on girders 1 anchored in the brickwork, it receives the bedplate 6, the central column 7, and the ring 8, the said ring 8 is arranged to rest on the bedplate 6 and receives the brackets 9 and supports various accessory mechanical parts.

The drive is obtained by means of a shaft 10 carrying a double set of fast and loose pulleys 11 and 12, the latter set for crossed belts so as to reverse the direction of movement by means of the device 13.

In this way this reversing is done with out using friction cones. The counter shafts 14 and 15 are also arranged on the bedplate.

The whole of these mechanical arrange-v ments insures perfect stability to the motions.

The arrangements allowing of dismantling the scraper arms are as follows:

The central shaft in two parts 16 and 17 is provided at its base with a cross bar 18, in the center of which is secured a ball bearing on which rests the shaft 16, 17. The ends of the cross bar 18 are connected to a cable 19 passing over rollers 20 and supporting at the other end a case 21 containing balance weights for the central shaft 16, 17 carrying the arms 22. This balance weight thus arranged below ground and as shown in Fig. 2, cannot cause an accident in the case ofa fall.

At the top of the part 17 of the central shaft is arranged a gland 23 supported by girders 24 in two parts connected by a key to the said gland and secured on the other hand to a pivot pin 25.

At the moment when it is desired to remove the central shaft complete with its arms, the said girders 2 1 are quickly disconnected from the gland and pivoted about the pin 25 and uncover the top of the furnace so as to enable the shaft 17 to be removed. 1

The part 17 of the cen ral shaft engages with the part 16 by means of tenons '26, moreover it is secured by four long bolts 27 passing through the part 17 inside and pressing together the two parts 16, 17 coupled together.

The operation of removal of the central shaft and of the arms 16, 17 22 is effected in the following manner:

Under the balance weight case 21 are placed two wooden checks of suitable thickness in order that the said case remains in the position which it occupied at the moment of stopping the furnace. The girders 24 of the gland 23 are pivoted at the upper part of the furnace and can be moved into the dotted line position Fig. 3 after having disconnected them.

Finally, the four bolts 27 are loosened in order to disconnect the parts 16, 17, and after attaching the upper end of the shaft 17 to a rotating pulley block, it is merely necessary to hoist the shaft 17 provided with its arms, causing it to turn during the hoisting to a corresponding extent so that it follows the pitch of the refractory helical soles.

The pulley block raises as Well the gland 23, Fig. 4, which naturally resumes its place during the lowering.

What I claim as my invention and desire to secure by Letters Patent is 2- 1. In a furnace of the type referred to, a two part shaft, arms mounted thereon, keys and screw-threaded rods connecting the said parts together, mechanism for driving said shaft arranged at the lower part of the furnace and means for disconnecting and removing the said shaft and arms.

2. In a furnace of the type referred to, a

shaft and arms,'a gland arranged-at the upper end of the shaft, guides pivoted to the outside walls and supporting said gland, mechanism for drivinmsaid shaft arranged at the lower part of tie furnace and means for disconnecting and removing the said shaft and arms.

3. In a furnace of the typereferred to, a two part shaft, arms mounted thereon, keys and screwthreaded rods connecting the said parts together, mechanism for driving said shaft arranged at the lower part of the fur-' EMILE CONSTANT BRAOQ.

Witnesses GnoReEs FAUGri, ROBERT FAUGii.

t, arms mounted thereon, keys 

